Draft Population Projections for Anguilla over the period 2002 to 2011

 

Introduction

Population projections are simply that, projections. They are not forecasts of what the population is expected to be but rather a mechanical model based upon assumptions about birth, death and migration rates. The number of births minus deaths gives the natural rate of increase of the population. Then numbers emigrating is subtracted from numbers immigrating to result in a net migration figure, which is added to the population adjusted for the natural rate of increase. Thus the projections are very sensitive to the assumptions made about migration into and out of Anguilla.

 

In countries with larger populations than Anguilla, population projections are given for each single year of age broken down by sex and are done for each year. Since Anguilla has no experience with population projections and their use, and given the wide fluctuations in death, birth and migration rates from year to year, these projections are based upon 5-year intervals and 5-year age groups broken down by sex to smooth out fluctuations in birth and death rates.

 

Births

The number of births that occurs is dependant upon the fertility rate of the population. In turn the overall fertility rate is dependent upon the number of women who are in their child-bearing years. For example, if there is a greater proportion of women in the age groups when women tend to have children, then there is a tendency for the country to have a higher fertility rate. Age specific fertility rates are expressed per 1,000 of women in the specific age group and the child-bearing years are normally considered to be 15 to 44 years.

 

 

The chart above shows that women in all age groups, with exception of 25 29 year olds have been experiencing slight growth in their fertility rates over the past 8 years. In general, however, they do fluctuate widely due to the small number of births in each age group. Therefore for the purposes of these projections, the average 3 year age fertility rates over the past 3 years have been used to project births over the next 10s.

Text Box: Average Age Specific Fertility Rates by Five-Year Age Groups over the Period 2000-02

Age group	19 & under	20-24	25-29	30-34	35-39	40&over
Fertility Rate	61.3	117.8	97.8	71.3	33.1	14.7


 

 

 

 

 


Fertility rates among teenagers are relatively high and may decline over the next 10 years as family planning programmes are targeted to teenagers. However for the purposes of these projections no change has been assumed over the next ten years.

 

The following tables shows the number of births by age of mother historically and also the number projected over the ten year period assuming the three year average age specific fertility rates. Note over the period 2002 6 the total number of births projected is 907 and over the 2007-11 period the number of projected births is 970.

 

Number of Births by Age of Mother, 1995 to 2002 and projections for 2002-6 and 2007-11

Year

Total

19 & under

20-24

25-29

30-34

35-39

40&over

1995

167

18

50

51

33

12

3

1996

161

23

40

44

33

14

7

1997

169

24

49

54

28

12

2

1998

155

27

29

38

34

20

7

1999

176

29

42

43

35

22

5

2000

193

37

48

42

43

17

6

2001

182

30

56

44

25

20

7

2002

169

23

42

41

40

16

7

 

 

Projections average births per year

 

 

2002-06

182

30

49

42

36

18

7

2007-11

194

36

59

42

32

17

8

 

Death

Deaths and death rates are dependent upon the age structure of the whole population, not just women. The chart below shows how death rates increase with age and have bee declining slightly in recent years among the older age groups.

 

 

For the purposes of these population projections it was decided to use the average death rates over the past 5 years by five year age group to forecast the total deaths. The rates are shown in the table below:

 

Age groups

Deaths over 5 years 1998-2002

Death Rates over 5 years using 2001 Population

Male

Female

Total

Male

Female

Total

0 - 4

3

1

4

0.005714

0.001825

0.003728

5 - 9

-

1

1

0

0.002037

0.001007

10 - 14

-

1

1

0

0.001745

0.00088

15 - 19

2

3

5

0.004193

0.00611

0.005165

20 - 24

3

3

6

0.008

0.007264

0.007614

25 - 29

3

3

6

0.006818

0.006928

0.006873

30 - 34

4

2

6

0.008097

0.00396

0.006006

35 - 39

4

1

5

0.00789

0.001876

0.004808

40 - 44

5

1

6

0.011655

0.002212

0.00681

45 - 49

7

2

9

0.019231

0.005714

0.012605

50 - 54

7

3

10

0.029661

0.012931

0.021368

55 - 59

7

5

12

0.042169

0.031847

0.037152

60 - 64

7

7

14

0.048611

0.04375

0.046053

65 - 69

14

9

23

0.08805

0.070866

0.08042

70 - 74

19

13

32

0.231707

0.100775

0.151659

75 - 79

19

22

41

0.292308

0.244444

0.264516

80 - 84

23

29

52

0.442308

0.58

0.509804

85 +

30

50

80

0.625

0.735294

0.689655

Total

157

156

313

0.027896

0.026887

0.027384

Using these death rates, the projected deaths are shown in the table below.

 

Deaths by Age Group, Actual Figures for 1998 to 2001 and Projections for annual averages for 2002-6 and 2007-11

Age

1998

1999

2000

2001

2002-6

2007-11

0 - 4

1

1

0

0

1

1

5 - 14

0

1

1

0

0

0

15-29

1

3

3

5

4

4

30-44

2

2

6

3

3

4

45-59

4

9

1

8

9

12

60-64

2

1

0

9

3

4

65-69

5

6

7

1

5

5

70-74

7

7

7

8

9

9

75-79

9

8

9

8

11

14

80-84

15

5

14

9

16

19

85+

16

15

21

15

30

28

Total

62

58

69

66

91

102

 

Migration

Migration is a net figure made up of those immigrating to Anguilla and subtracting the out migrants. There are no figures available for either and they are computed as a residual after subtracting deaths and adding births to the populations available each 10 years from the census. The residual is more or less equally distributed among the inter-censal years. The following table shows the derived net migration from Census years 1992 to 2001.

 

Net Migration Derived from the Census Population Counts and the Natural Rate of Increase of the Population

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

256

150

170

53

226

230

178

201

261

301

 

Immigration is made up of returning Anguillians, who may be returning for work or to retire, foreigners working on work permits and retirees who are few in number. The emigrants are mainly made up of those who are in Anguilla on temporary work permits, those in their late teens or early twenties leaving to study and Anguillians who leave to seek work, these are becoming fewer in number.

 

After discussions with the Permanent Secretary to the Chief Minister, it was decided to use a flat figure of 200 net migrants per year with half of this number being males in the prime working age group of 25 to 44 years. The remaining 100 migrants were distributed almost equally among the other age and sex groups.

 

Since the number of net migrants is just under double the natural rate of increase of the projected population (106 per year), immigration policy has a much greater effect upon the population projections than does the natural rate of increase. The distribution of net migrants by age used in the projections is given below:

 

Assumptions of Net Migration by Age Group, low migration assumption

Age Group

Males

Females

Total

0 - 4

3

3

6

5 - 9

3

3

6

10 - 14

3

3

6

15 - 19

3

3

6

20 - 24

3

3

6

25 - 29

25

4

29

30 - 34

25

4

29

35 - 39

25

4

29

40 - 44

25

4

29

45 - 49

3

3

6

50 - 54

3

3

6

55 - 59

3

3

6

60 - 64

3

3

6

65 - 69

3

3

6

70 - 74

3

3

6

75 - 79

3

3

6

80 - 84

3

3

6

85 +

3

3

6

Total

142

58

200

 

A second projection was done assuming a net migration of 400 people per year, being evenly distributed between the two sexes and more or less distributed evenly among the age groups with slightly less in the older age groups as follows:

 

High Migration Assumption

Age Group

Male

Female

Total

0 - 4

75

75

150

5 - 9

75

75

150

10 - 14

75

75

150

15 - 19

75

75

150

20 - 24

75

75

150

25 - 29

75

75

150

30 - 34

79

79

158

35 - 39

78

78

156

40 - 44

78

78

156

45 - 49

75

75

150

50 - 54

75

75

150

55 - 59

75

75

150

60 - 64

15

15

30

65 - 69

15

15

30

70 - 74

15

15

30

75 - 79

15

15

30

80 - 84

15

15

30

85 +

15

15

30

Total

1000

1000

2000

A third migration assumption was made which is called the medium level migration assumption. It is assumed that net migration levels are at 300 per year, evenly distributed throughout the age groups and of both sexes.

 

Medium Level of Migration

 

Age Group

Male

Female

Total

0 - 4

42

42

84

5 - 9

42

42

84

10 - 14

42

42

84

15 - 19

42

42

84

20 - 24

42

42

84

25 - 29

42

42

84

30 - 34

42

42

84

35 - 39

42

42

84

40 - 44

42

42

84

45 - 49

42

42

84

50 - 54

42

42

84

55 - 59

42

42

84

60 - 64

41

41

82

65 - 69

41

41

82

70 - 74

41

41

82

75 - 79

41

41

82

80 - 84

41

41

82

85 +

41

41

82

Total

750

750

1500

 

 

Population Projections

The low migration assumption population projections show the rate of increase of the population averages 3.1% per year between 1992 and 2001, 2.5% between 2001 and 2006 and then 2.3% between 2006 and 2011. The percentage of the population of school age declines from 28% in 2001 to 22% in 2011. The proportion of prime working stays the same at close to 33% in spite of the net migration assumption which favoured this age group. The largest increase is among those aged 45 to 64 which move from making up 16% of the population to 23% by the end of the projection period of 2011. This is due to the fact that 33% of the present population is at present in the 25 44 age group and as they age they will move into the next age group which only represents 16% of the population at present.

 

The alternative high migration scenario shows an annual average rate of increase going from 2.5% in 1992-2001, then to 4.2% in2001-6 and 3.6% in 2006-11. The distribution of the population shows the age group 45-64 moving from 16% in 2001 to 20% and then 25% by 2011.

 

 

 

Distribution of the Population By Age Group, actual 1992 and 2001 and projections for 2006 to 2011 based upon a low migration and high migration assumptions.

 

Actual Low migration High Migration Medium Migration

Age groups

1992

2001

2006

2011

2006

2011

2006

2011

0 - 14

2,735

3,202

3,058

3,094

3,418

3,809

3,220

3,412

15 - 24

1,558

1,756

2,151

2,228

2,391

2,707

2,259

2,443

25 - 44

2,766

3,793

4,257

4,625

4,297

4,813

4,013

4,253

45 - 64

1,090

1,809

2,447

3,324

2,807

4,042

2,661

3,634

65+

811

870

971

1,078

971

1,078

1,231

1,493

Total

8,960

11,430

12,884

14,349

13,884

16,449

13,384

15,236

Percentage Distribution by Age Group: Low migration High Migration

 

Age groups

1992

2001

2006

2011

2006

2011

2006

2011

0 - 14

31%

28%

24%

22%

25%

23%

24%

22%

15 - 24

17%

15%

17%

16%

17%

16%

17%

16%

25 - 44

31%

33%

33%

32%

31%

29%

30%

28%

45 - 64

12%

16%

19%

23%

20%

25%

20%

24%

65+

9%

8%

8%

8%

7%

7%

9%

10%

Total

100%

100%

100%

100%

100%

100%

100%

100%

Growth Rates: Actual Low migration High Migration

 

age groups

1992

2001

2006

2011

2006

2011

2006

2011

0 - 14

 

17.1%

-4.5%

1.2%

7%

11%

1%

6%

15 - 24

 

12.7%

22.5%

3.6%

36%

13%

29%

8%

25 - 44

 

37.1%

12.2%

8.6%

13%

12%

6%

6%

45 - 64

 

66.0%

35.3%

35.8%

55%

44%

47%

37%

65+

 

7.3%

11.6%

11.0%

12%

11%

41%

21%

Total

 

27.6%

12.7%

11.4%

21%

18%

17%

14%

One Year ave growth

 

3.1%

2.5%

2.3%

4.2%

3.6%

3.4%

2.8%


Recommendations

In calculating these projections it became clear that there are two areas which require work in order to be able to do more useful projections. They are:

 

 

 

 


Actual Population by Five Year Age Groups and Sex, 1992 and 2001

 

Age groups

1992

2001

 

Male

Female

Total

Male

Female

Total

0 - 4

494

492

986

525

548

1,073

5 - 9

463

481

944

502

491

993

10 - 14

404

401

805

563

573

1,136

15 - 19

387

373

760

477

491

968

20 - 24

409

389

798

375

413

788

25 - 29

470

427

897

440

433

873

30 - 34

378

393

771

494

505

999

35 - 39

326

323

649

507

533

1,040

40 - 44

234

215

449

429

452

881

45 - 49

169

147

316

364

350

714

50 - 54

148

146

294

236

232

468

55 - 59

129

127

256

166

157

323

60 - 64

100

124

224

144

160

304

65 - 69

108

121

229

159

127

286

70 - 74

104

112

216

82

129

211

75 - 79

83

101

184

65

90

155

80 - 84

50

58

108

52

50

102

85 +

17

57

74

48

68

116

Total

4,473

4,487

8,960

5,628

5,802

11,430

 

Population Projections from 2002 to 2006 and 2007 to 2011 by Five Year Age Groups and Sex Assuming Migration of 200 Per Year Concentrated in Prime Working Age Group and Male

 

Age groups

 

2006

 

 

2011

 

 

Male

Female

Total

Male

Female

Total

0 - 4

466

467

934

499

501

1,000

5 - 9

540

562

1,102

481

481

963

10 - 14

517

505

1,022

555

576

1,131

15 - 19

576

584

1,160

530

517

1,047

20 - 24

488

502

991

586

595

1,181

25 - 29

497

430

928

610

519

1,129

30 - 34

561

451

1,013

618

448

1,067

35 - 39

615

524

1,139

682

470

1,153

40 - 44

626

552

1,178

733

543

1,276

45 - 49

436

464

900

629

564

1,193

50 - 54

368

360

729

438

473

911

55 - 59

241

240

481

368

364

732

60 - 64

173

165

338

244

244

488

65 - 69

146

164

310

173

168

341

70 - 74

137

129

273

127

162

293

75 - 79

73

112

185

112

113

231

80 - 84

51

53

106

56

62

121

85 +

53

46

98

54

41

93

Total

6,565

6,312

12,884

7,496

6,843

14,349

Population Projections from 2002- 2006 and 2007-2011 by Five Year Age Groups and Sex(Migration of 400 Per Year)

 

 

 

2001-6

 

 

2006-11

 

 

Age groups

Male

Female

Total

Male

Female

Total

0 - 4

526

527

1,054

617

619

1,236

5 - 9

600

622

1,222

601

601

1,203

10 - 14

577

565

1,142

675

696

1,371

15 - 19

636

644

1,280

650

637

1,286

20 - 24

548

562

1,111

706

715

1,420

25 - 29

447

485

933

619

634

1,253

30 - 34

515

510

1,026

523

562

1,085

35 - 39

568

582

1,150

589

587

1,177

40 - 44

579

610

1,189

639

659

1,298

45 - 49

496

524

1,020

643

681

1,324

50 - 54

428

420

849

556

593

1,148

55 - 59

301

300

601

485

482

967

60 - 64

173

165

338

301

302

603

65 - 69

146

164

310

173

168

341

70 - 74

137

129

273

127

162

293

75 - 79

73

112

185

112

113

231

80 - 84

51

53

106

56

62

121

85 +

53

46

98

54

41

93

Total

6,855

7,022

13,884

8,127

8,313

16,449

Population Projections from 2002- 2006 and 2007-2011 by Five Year Age Groups and Sex(Migration of 300 Per Year)

 

 

 

2001-6

 

 

2006-11

 

 

Age groups

Male

Female

Total

Male

Female

Total

0 - 4

493

494

988

550

552

1,102

5 - 9

567

589

1,156

535

535

1,071

10 - 14

544

532

1,076

609

630

1,239

15 - 19

603

611

1,214

584

571

1,155

20 - 24

515

529

1,045

640

649

1,289

25 - 29

414

452

867

554

568

1,121

30 - 34

478

473

952

453

492

945

35 - 39

532

546

1,078

517

514

1,031

40 - 44

543

574

1,117

568

587

1,155

45 - 49

463

491

954

575

613

1,187

50 - 54

395

387

783

491

527

1,018

55 - 59

268

267

535

421

417

838

60 - 64

199

191

390

296

296

592

65 - 69

172

190

362

222

219

441

70 - 74

163

155

325

173

212

389

75 - 79

99

138

237

156

158

321

80 - 84

77

79

158

96

99

198

85 +

79

72

150

80

67

145

Total

6,605

6,772

13,384

7,520

7,706

15,236

Percentage of the Population who is Anguillian

 

 

Male

Female

Total

 

0 - 14

76%

74%

75%

 

15 - 29

76%

73%

74%

 

30 - 44

65%

65%

65%

 

45 +

77%

76%

76%

 

Total

73%

72%

73%